Electric regulator



Jan. 2, 1945. L. R. NIXON ELECTRIC REGULATOR Filed July 19, 194:5

3 Sheets-Sheet 1 Jan. 2, 1945. L. R. NIXQN 2,366,283

' ELECTRIC REGULATOR Filed July 19, 1943 s Sheets-Sheet 2 Jan. 2, 1945.L. R. NIXON ELECTRIC REGULATOR Filed July 19, 1943 3 Sheets-Sheet 3Patented Jan. 2, 1945 UNlTED ELECTRIC REGULATOR Leslie Reginald Nixon,London, England, assignor to J. Stone & Company Limited, Deptford,

England, a British joint-stock company Application July 19, 1943, SerialNo. 495,333 In Great Britain June 8, 1942 '7 Claims.

This invention relates to improvements in electric regulators of thecarbon pile type and is concerned with regulators wherein the magnetarmature operates in opposition to a pile-compressing spring or springs.In such regulators wherein a clapper armature is employed the tiltingpile is not possible at all unless the line of the hinge is completelyoutside the area of the pressure plate. Further, any unevenness in. thestressing of the pile results in uneven current distribution andtherefore heating over the surface of the rings and this causes the lifeof the pile to be shortened. The object of the present invention is toensure, by simple means, the stressing of the pile only in the directionof its axis and the limiting of the movable end of the pileapproximately to a straight line movement in the direction of such axis.

According to this invention, a presser device engaging the movable endof the pile is guidingly supported so that it is constrained to moveapproXimately in. the direction of the axis of the pile only, and thesaid presser device is connected by flexible members with the armaturedevice so that no unbalanced or tilting force can be applied to thepresser device. The guiding support of the presser device isadvantageously resilient so that the presser device is floatinglysupported and able to adjust itself to any slight irregularity.

In order to enable the invention to be readily understood, reference ismade to the accompanying drawings, wherein:

Figure 1 is a perspective view illustrating the application of thepresent improvements to a regulator in which the armature of the magnetis carried by a hingedly mounted plate or clapper.

Figure 2 is a diagrammatic side elevation mainly useful for explainingthe mounting of parts seen in Figure 1 but also showing a modified formof armature.

Figure 3 is a sectional side elevation illustraton the line IVIV inFigure 3 and as viewed from the right-hand side of that figure.

Figure 5 is a sectional plan View of parts seen in Figure 3, and

Figure 6 is a sectional elevation the section being taken on the lineVI-VI in Figure 5 and as viewed in the direction indicated by the arrowheads.

Referring to Figure 1, aa is a laminated magnet structure of anelectro-magnet, a being the core part and a being one of two side partsdisposed externally of the energizing coil 1 Between the core part a andside parts a there are tWo parallel polar gaps I) only one of which isvisible in Figure 1. The armature c is an inverted U-shaped piecepresenting two blades 0 for entry into respective polar gaps b when themagnetization is sufliciently powerful for over coming the usual springresistance. In Figure 1, the edges 0 of the blades 0 are contoured withcurves to give a predetermined magnet pull characteristic. In Figure 2,a similar armature piece has the corresponding edges 0 of its blades 0contoured with an inclined straight line for giving a differentcharacteristic.

Referring to Figures 1 and 2, the inverted U- shaped armature piece isstraddled and fixed upon a narrow end portion of a hingedly mountedplate or clapper d. The opposite and wide end of the plate d is formedwith lateral extensions d for the attachment of two pairs of bladesprings e and i, one pair at each side. Frame parts 9 of the regulatorserve for the mounting of the springs cf in the following manner: Theblade springs e which are perpendicular to the plane of the frame bars 9are fixed at their ends by screws to respective end surfaces of the barsg and extensions d The blade springs f which are parallel with the barsg are fixed at their ends by screws one end being fixed on the uppersurface of a bar ,1 and the other end being fixed against the undersurface of an extension d The blades cf of a pair thus intersect oneanother at right angles, and, as will be clear from Figure 1, the blade1 of a pair may be slotted to permit the associate blade e to passthrough it. The blades of thus provide, in known manner, hinge mountingsgiving a fulcrum axis a: Figure 2 at the point of intersectionaforesaid. The lateral extensions d are formed with steppedlongitudinall extending lugs 11 for the attachment of a tension coilspring or springs, not shown. As will be apparent, particularly fromFigure 2, such tension springs act at one side of the fulcrum axis :0with a short lever arm to put the pile h under compression. The armaturepiece operating at the other side of the axis as, and with a much longerlever arm, is effective for opposing the action of the tension springsand for decompressing the pile h.

In Figure 1, the pile h is shown in a vertical position but in actualuse the regulator would be turned through 90 so that the pile h would besupported horizontally. When, therefore. parts are hereinafter describedas vertical or horizontal, these terms are used purely relatively andwhen having regard to the drawings. The so-called fixed end of the pile,not seen in the drawings, is supported by an adjustable screw abutmentin known manner, adjustment of this abutment being effective for movingthe pile h bodily endwise and so adjusting the position of the clapper dand armature c and the tension of the pile-loading springs. The movableend of the pile, seen in Figure 1. is engaged by a presser ring 7 whichis connected with the clapper as hereinafter described. The presser ring7' is supported by a vertical stiff guide strip k, the upper end of thelatter being folded and bent horizontally and the folded part beingattached by a screw to the flat end of 2. lug :i on the ring 7' asshown. The horizontally bent top part k of the strip is is fixed, as bythe rivet shown, upon a flexible diaphragm 0r bow spring Z. The bottomend of the strip is is bent horizontally to form a foot 7: which issecured upon a lower bow spring 1 By this means, the presser ring :i issupported so that it is movable approximately in the vertical directiononly but with the ability to adjust itself for the application of purelyaxial pressure to the pile h. The ring 9' is formed with lateral lugs 7'for the attachment of the upper ends of flexible connectors which maytake the form of flexible metal strips m, Figures 1 and 2, the lowerends of these strips m being attached by screws m to the drop arms 01depending from the wide end of the clapper. The flexible connectors mare thus attached to the short arm of the double armed lever provided bymounting the clapper d to hinge about the fulcrum axis at and owing tothe use of the drop arms (1 the points of attachment m are beneath thelevel of such axis 1:. Thus, when the armature c is in the oil" positionshown, the mechanical advantage of the tension springs attached to thelugs 11 and acting on the presser ring 7' through the connectors m is ata maximum. This is explained by the fact that the points of attachment mon the drop arms d may be regarded as being disposed similarly to acrank pin near to a dead centre. The attraction of the armature 0 intothe polar gaps and the consequent pivotal movement of the clapper it,results in an elevation of the short arm of the lever and the movingaway of the points of attachment m from the axis x, whereupon thetension springs compress the pile with reducing mechanical advantage.With the arrangement above described, the pile h is constrained to move,or be compressed, approximately axially and without incurring frictionfrom pivot pins, sliding guides and the like.

The present improvements are also applicable to regulators of the typewherein a magnet operates a lever which is connected with a presserdevice at the movable end of a pile. In such regulators, and asillustrated in Figures 3 to 6, the magnet armature n, Figure 3, may beof the rotor type mounted on a shaft 0. A sector go fixed by its hub onthe shaft 0 has connected to it one end of a steel tape q the oppositeend of the latter being connected with a coil spring 1'. The magnetpoles n attract the armature n against the resistance of the spring 1'and as the armature turns in one direction or the other, the tape qwraps or unwraps on or from the sector p. An arm s extending from thehub of the sector p is fitted with a pivot pin s and a block or link ifpivotal about such pin s has connected to it one end of a steel tape orflexible connector u, the other end of the latter being connected with abracket '0 on the end of a lever w movable about a pivot w This pivot issupported by bracket parts a: bent up from a frame part a: as shown inFigure 4. On a hub part of the lever 20 there is pivotally mounted atwo-armed lever comprising a long arm 1/ and a short arm 1 This lever yyconsequently turns about the same pivot axis as the lever w. At the freeend of the long arm y there is mounted a split nut block 2 in which anabutment screw I is adjustable. One end of the screw I is formed with amilled head i which abuts against one end of a compression spring 2, theopposite end of this spring being supported against an arm on one end ofthe bracket 1;. The opposite end of the screw i extends to within asmall distance of an arm on the opposite end of the bracket v. When thescrew I has been adjusted to vary the compression of the spring 2 and toalter the amount of clearance between its free end and the adjacent armof the bracket 12, it can be fixed in its adjusted position bytightening a screw .2 which causes the split nut block 2 to grip thescrew At the free end of the short arm there is fixedly connected byscrews one end of a steel tape or flexible connector 3, the opposite endof the latter being fixedly connected with a stiff bar 4. One endportion 4 of this bar is bent at right angles for attachment to aspringy metal diaphragm 5 the other end portion 4' being bent to formone half of a Y-shaped fork, the other half of such fork being a part Mwhich is secured by a screw 4 to the part 4', the connector 3 beingclamped between the two parts and held by the screw 4 as shown. The endsof the fork parts 4*, 4 are bent at right angles at 4 for enabling suchends to be bolted to a springy metal diaphragm 6, as seen clearly inFigures 3 and 5. The diaphragm 6 is supported by attachment to a bentpart m of the frame plate a: but the diaphragm 5 is supported byattachment to a spider 1 supported by a leg 8 connected with the framingof the regulator. Through the fork members 4 and 4 there is passed apivot pin 9 which may be more or less stitlly clamped by a clampingplate to against a presser plate H. The latter, as seen best in Figure6, is widened at each end for attachment by screws I! to two diamondshaped presser plates 13 which are active against the movable ends ofthe two carbon piles Id. The immovable ends of the piles I are supportedagainst fixed abutment plates 18, Figure 5, mounted on the framing ofthe regulator. Each of the presser plates I3 is provided with a terminal19, Figures 5 and 6, for the connection of an electrical conductor andeach of the shutment plates l8, Figure 5, is provided with a similarterminal 19 When the magnet coil 20 of the regulator is not suilicientlyenergized for causing its poles n to attract the rotary armature n fromthe position seen in Figure 3, the piles ll are under maximumcompression applied in the following manner: The spring r pulls on thesector p tending to turn the latter and the armature n clockwise, butthis clockwise movement is limited by an adjustable stop 2 I, Figure 3.The consequentclockwise tendency of the arms s caused the link if topull on the flexible connector u and this pull being transmitted to thebracket 22, the latter compresses the spring 2 and this presses theabutment screw I, l leftwardly. Thus the long lever arm y is pressedleftwardly and the short arm has a rightward tendency, thereby puttingthe flexible connector 3 under tension. The rightward pull thus appliedto the bar 4 is transmitted by the pivot pin 9 see also Figure 5, to thepresser plate H which in turn applies the effort to the two presserplates [3 which compress the piles i4. Owing to the pivot pin 9 thepresser plate ii is able to adjust itself about this joint and therebyto equalise the degree of compression applied to each of the two pilesl4.

When the magnet coil 20, Figure 3, becomes sufficiently strong forcausing its poles n to attract the armature n against the resistance ofthe spring r, the armature moves counter-clockwise into the polar gap.The sector p moves similarly and winds on the tape q, and the arm 8 alsomoving counter-clockwise slackens the flexible connector u, so that thebracket '0 and its lever to can move to the right in Figure 3. At first,this movement permits the spring 2 to ex pand until the left hand arm ofthe bracket comes against the abutment screw l whereupon the lever w andlong lever arm y swing rightwardly in company, and the short lever arm yswings leftwardly to decompress the piles. Under maximum pilecompression conditions, the spring 1- holds the armature against thestop 2! as aforesaid and there is a clearance between the end of theabutment screw I and the left-hand arm of the bracket 2) as seen inFigure 1. Consequently, in such conditions, the compression of the pilesis due to the spring 2 reacting between the bracket 12 on the lever wand the abutment screw 1 carried by the long lever arm y. The maximumcompression of the piles is consequently very easily adjusted by turningthe milled head I for increasing or decreasing the compression of thespring 2.

It will now be seen that with the bar 4 mounted for guidance in themanner described and with the flexible connectors employed fortransmitting the efforts purely axial pressures are applied to the pileswithout incurring variable friction losses and in a thoroughly reliablemanner.

I claim:

1. An electric regulator of the carbon pile type wherein anelectromagnet is operative for decompressing the pile, comprising incombination a presser device engaged with the movable end of the pile,guiding means disposed externally of the pile and connected with saidpresser device and movable only in a direction parallel with the axis ofthe pile, and a flexible operative connection between the armature ofsaid electro-magnet and said presser device, said connection beingmaintained under tension throughout the greater part of its range ofoperation.

2. An electric regulator of the carbon pile type wherein anelectromagnet is operative for decompressing the pile, comprising incombination a presser device engaged with the movable end of the pile, astiif guide bar operatively connected with said presser device anddisposed externally of the pile and parallel with the axis thereof,

springy supports connected with the ends of said guide bar andpermitting longitudinal movement only of said guide bar and a flexibleoperative connection between the armature of said electromagnet and saidpresser device, said connection being maintained under tensionthroughout the greater part of its range of operation.

3. An electric regulator of the carbon pile type wherein anelectro-magnet is operative for decompressing the pile, comprising incombination a presser device engaged with the movable end of the pile, astiff guide bar operatively connected -With said presser device anddisposed parallel with the axis of said pile, springy supports connectedwith the ends of said guide bar and permitting longitudinal movementonly of said guide bar, and flexible metal tapes constituting operativeconnections between the armature of said electro-magnet and said presserdevice.

v 4. An electric regulator of the carbon pile type wherein anelectro-magnet is operative for decompressing the pile, comprising incombination a presser device engaged with the movable end of the pile, astiff guide bar operatively connected with said presser device anddisposed parallel with the axis of said pile, springy supports connectedwith the ends of said guide bar and permitting longitudinal movementonly of said guide bar, a drop crank device operatively connected withthe armature of said magnet, and flexible metal tapes connected betweensaid drop crank device and said presser device.

5. An electric regulator of the carbon pile type wherein anelectro-magnet is operative for de-- compressing the pile, comprising incombination a lever system operatively connected with the armature ofsaid electro-magnet, a presser device engaged with the movable end ofsaid pile, a stiff guide bar operatively connected with said presserdevice and disposed parallel with the axis of said pile, springysupports connected with the ends of said guide bar and permittinglongitudinal movement only of said guide bar, and a flexible metal tapeconstituting an operative connection between said lever system and saidguide bar.

6. An electric regulator of the carbon pile type comprising incombination a pile, a presser device engaged with the movable end ofsaid pile, a stifi guide bar operatively connected with said presserdevice and disposed parallel with the axis of said pile, springysupports connected with the ends of said guide bar andpermittinglongitudinal movement only of said guide bar, a two arm leverpresenting long and short arms, a flexible connection between the shortarm of said lever and said guide bar, and a second flexible connectionbetween the long arm of said lever and the armature of theelectro-magnet.

7. An electric regulator as claimed in claim 5, and wherein the leversystem comprises a single arm lever and a two-arm lever, said leversbeing movable about a common pivot, one arm of the two arm lever beingflexibly connected with the stiff guide bar and the other arm of suchlever having an adjustable screw abutment, the single arm lever beingfitted with a compression spring operative against said screw abutmentand constantly tending to close a gap between said screw abutment and anabutment of said single arm leverand the last-named lever being flexiblyconnected with the armature of the electro-magnet.

LESLIE REGINALD NIXON.

